1. Field of the Invention
The present invention relates to a touch sensor panel with improved touch sensitivity and a method of manufacturing the same, and more particularly, a touch sensor panel capable of precisely determining a touch location with a given area of electrodes, reducing the number of channels required, reducing the influence of noise and improving visibility of displayed image.
2. Discussion of the Related Art
With the widespread distribution of mobile phones equipped with touch screens and the commercialization of various types of smart phones, touch sensing technology has been vigorously researched.
Touch screens, which are one of the most common touch sensing devices, are classified as resistive, capacitive, ultrasonic, or infrared (IR) touch screens according to their operating methods. Capacitive touch screens, in particular, have been widely adopted in various fields due to their high durability, long lifetime, and capability of supporting multi-touch function.
A capacitive touch screen may detect a touch location based on a capacitance variation resulting from a user's touch on the front surface of a display window thereof. Thus, the capacitive touch screen may not be able to properly detect a touch input when the touch input is made by, for example, a stylus pen, which accompanies a slight capacitance variation.
Given that the structure of a touch sensor panel is an important factor for properly detecting a variation in capacitance, it is beneficial to develop a touch sensor panel capable of detecting a touch input (e.g., a touch input made by a stylus pen or fingernail) that accompanies a slight capacitance variation.
It is also beneficial to develop a touch sensor panel capable of precisely determining the location of a touch input without distorting touch sensing signals.
In the meantime, a related-art electrode architecture for detecting a multi-touch input has a double-layer structure consisting of two layers, and each of the two layers includes a plurality of electrode lines arranged along an X direction and a plurality of electrode lines arranged along a Y direction. Since the related-art electrode architecture is required to have an electrode pattern formed for each of the two layers, the fabrication of the related-art electrode architecture is complicated, and the manufacturing cost of related-art electrode architecture is generally high. To address the problems associated with the related-art electrode architecture, the applicant of the subject application has developed a single-layer electrode pattern capable of detecting a multi-touch input. In the single-layer electrode pattern, however, the distance between adjacent electrodes or adjacent internal wirings is so small that electrodes connected to different channels may be short-circuited upon occurrence of, for example, etching error, or infiltration of foreign materials during a manufacturing process, and that product defects may occur. For example, to reduce such product defects, the distance between electrodes may be widened. However, in this example, an electrode pattern may undesirably become visible to the naked eye due to the difference between the transmittance of etched parts and non-etched parts, and thus, the visibility of displayed image may deteriorate. Therefore, a method is needed to provide a touch sensor panel capable of preventing electrodes connected to different channels from being short-circuited due to etching error or the infiltration of foreign materials, reducing a defect rate, and improving visibility regardless of the difference between the transmittance of electrodes and non-electrodes.